Machine tool



April 16, 1940. KOLB AL 2,197,308

MACHINE TOOL Filed April 22, 1938 4 Sheets- Sheet 1 Af mfiy FIG"? Inreni013 AM 16, 1940. A; KOLB HAL 2,197,308

' MACHINE T001.

Filed April 22, 1958 4 sheets-sheet 2 April 16, 1940. A. KOLB- ET ALMACHINE TOOL Filed April 22, l938 4 Sheets-Sheet 3 April 16, 1940.

A. KQ LB El AL MACHINE "soon FIGS].

\V 1 I Al Patented 1920 UNIT-El) srA'rE-s PATENT oF cs piicaflo'n April2t, 1938, Serial No. 203,888 A, In Germany July 0, 19:5

Claims. (CI. 51-185) Thisinvention relates to machine tools-and moreparticularlytomachinetoolsinwhichamagnifiedimageofthecuttingtoolandtheworkpiece profiles, at the pointwhere the tool and the work piece engage, is produced by illumination,and checked with a diagram card.

Ascomparedwithmschinetoolsinwhichthe position of the toolwithrespecttothework piecemachinetools is observed through a microscope, mof the type referred to have the advantages that the operators eye, oreyes, is not strained, and ,thattheu.-;ii-.- several persons at the sametime, for instance, by

It is an object of the improvedmachine tool .To this holding a instance.a lathe tool and awork piece to be ground, or a grinding wheel and afiat templet to be ground by the wheel-with means for illuminating thetool and the work piece at the point where they engage, and with meansfor imparting relative feeding movement to the tool and the work piecein the plane of the shadow image of the profiles of the tool and thework piece which is produced by such illumination at the point where thetool and the work engage; 3" means are provided for the image and for.projecting the a screen, for instance, a. plate of ground glass,wheretheimageischeckedwithadiagramcard. The illumination is preferablyefiectedby a bundle of parallel light rays which preferably is at anangle of 90 degs. to the plane of thefeeding movement. By these means,the profiles. of the tool and the work piece, viewed from that sidewhich is opposite the source of ill pref rab y paralleL-light, areclearly defined. The shadow image of the profiles is projectedontoascreemsuchasapane otground arranged preferably at right angles tothe direction of [the light, and enlarged, as required for r theprofiles, and exact ina-* chining of the. work. piece, by an objectivearranged at the rear of the pane, as viewed from the tool and the work.projected against the, other screen referred to where it is checked, asdescribed.

Other objects of the invention will appear from the followingspecification, with reference to the accompanying drawings in whichseveral embodiments of the invention are illustrated more 0;? a less atial vbv way of invention to provide an of the type referred to. end, incomlanaflon with means for cutting 'tool and a 'work piece-formagnifiedimageagainst- A A control The magnified imageis;

In the drawings Fig. l is a tie elevation, and

Fig.2isadiagrammaticplanvlempsrtlyiii section, of a precision lathewhere-the image of r the profiles is magnified by an objective at the 5rear of the ground glass pane.

Fig. 3 is a diagram showing the magnifying objective'arranged in frontof the pane. Fig. 4 is a sectional elevation of a combination of slidesand rotary members for supporting the 10 tool or the work piece, andFig. 5 is a section of the combination,-taken at right angles to.thesection in Fig. 4, and viewed from the left in figure;

Fig. 6 is a sectional diagrammatic elevation of 15 a mechanism -foroperating a pair of driving shafts forming part of the on illustratedinFksiandS.

view of Fig.- 6.

Referring-now to the drawings, and first to Figs. 1 and2, this precisionlathe is equipped with afoundation frame, or casing, i a box. An uppercross slide 3, and a. lower-cross slide 2; are mounted on the top plate54 of the box' I, andtheuppercrossslidetsupportsalathetoolt. so Theslidesare operated by hand wheels 4 and 5 on control shafts} and 1,respectively. The control in is illustrated only diagrammaticallyinElgs.1and2andisshownwiththecontrol shafts arranged at opposite sides of thebox I. 35

mechanism equipped with a pair of be dewherethe tool 3 engages source oflight is'surrounded bya reflector Ii and its rays are. collected and-directed toward the said point as a bundle ll of parallelrayaby a lensI at the lower end of the lamp II. The 50 profilm of tool 8 and the workpiece 8 are so illuminated by the bundle il that they appear clearlydefined if viewed against the lamp it, i. e., from belowxin 1. Q

Insertedinaholeofthehpplatellisthe."

tubular upper end l8 of a camera 20. The shadow image of the profilesappears in its own size, 1. e., without magnification, on a screen [8,normally a ground glass plate, in the camera 28. Arranged at the rear ofthe screen i9, as viewed from the lamp l3, or below the'screen, asarranged in Fig. 1, is a magnifying objective 2| which projects theimage onto an inclined mirror 22 at the bottom of the box I, and themirror reflects the image against an inclined screen 23 which mayalso-be a pane of ground glass, and is arranged in a convenient positionforobservation by the operator. In Fig. 2, theprofile' 8' of thetool 8,and the profile 9' of the work piece, are indicated by the shaded areas.A drawin or diagram card whose contour is indicated by the dotted line24 in Fig. 2, is secured to the inclined screen 23 by suitable means,not shown. This diagram card is drawn to the same scale as the magnifiedprofile image. In Fig. 2, the righthand portion of the work piece 9 hasalready been machined to size .and the operator now begins on theleft-hand portion which he must turn down .as far as the dotted line 24.I

If desired, the in'terengaging parts, i. e., the tool and the workpiece,may be exchanged; the tool 8 being replaced by a work piece, forinstance,

"a fiat templet, and the work piece 9 being replaced by a rotary tool,suchas a milling cutter, or grinding wheel. It is also possible toprovide guides in which the headstock ill, with the part-- work piece ortoolwhich it supports, is shifted or reciprocated vertically in parallelrelation to the bundle of parallel light rays ll.

Instead of arranging a horizontal screen l8 in the camera 28, it mightbe provided with an inclined screen, and with a mirror for deflectingthe image to the inclined screen. The image is then magnified, asdescribed. 7

Another possibility is that of dispensing with the second screen 23, andof projecting the mag-,

nified image of the profiles directly against a large screen like 23. Anoptical arrangement of this type is shown in Fig, 3 where the objective2| whose focal plane 26-26 coincides with the plane :in which therelative feeding movement of the parts 8 and 9 occurs, is placed betweenthe point where the parts engage each other,,and a large screen 25 onwhich the magnified imageof the profiles at the point is projected.

The system which has been described, is favorable with respect to thelight intensity required, as it has only one light-absorbing screen butit involves certain difiiculties if one of the parts, for instance, thework piece 9, a grinding wheel, or a milling cutterjreplacing the workpiece, is reciprocated vertically, as indicated by the arrows 21. If abundle ll of parallel rays projects the profile image on the screen l9,Fig. 1, and the image is then magnified, vertical movement of the partobviously has no influence on the definition of the image, but this isnot so when the image is magnified before being projected on the screen,as in Fig. 3, for the outline of the part 9 is obviously sharply definedonly when the axis of the part is in the focal plane 26-28.

Therefore, if light intensity is a secondary consideration, and one ofthe parts is reciprocated vertically, the system with the bundle i1of'parallel rays and the two screens l9 and 23, as illustrated in Figs.1 and 2, is preferable. The tool or the work piece, or both together,-may be recipro'cated vertically and in parallel relati n to the bundleH, as is the rule in reciprocating grinding machines, and it does notmake a difference if the distance of the part, or parts, from the plane26-26. varies, while in the arrangement according to Fig. 3 the image ofthe part, or parts, lacks definition whenever the part is not in thefocal plane 28-26.

It has been found that refractions of light occur at the edges ofthegrinding wheels, particularly those for grinding flat templets, andspoil the definition of the magnified image This drawback is eliminatedby using black wheels. Preferably, the grinding wheels are blackenedthroughout their substance. Either a substance is used which-has-a blackcolor, or it is colored black, or the binder, or binders, are black, orare colored black. Another possibility is impregnation of the wheelswith black color.

Instead of placing a drawing, or diagram card, on the screen 23 or 25,the diagram may be drawn on the screen itself. The usual magnificationis times.

As mentioned, it is a particular advantage of the invention that themagnified image on thescreen can be seen bys great number of persons ata time and without any effort or strain, as the persons are notcompelled to apply their eyes to the eye piece of a microscope. 1

For the convenience of the operator, it is desirable that the handwheels for adjusting the tool or the work piece through the medium ofcross slides, should be positioned in a fixed position with respect tothe screen on which the magnified image appears, and easily accessible.

These conditions are fulfilled in the arrangement which will now bedescribed with reference to Figs. 4 to 9.

Referring first to Figs. 4 and 5, the tool, or the work piece, issecured to the topmost slide 4| of a unit comprising, besides the topslide, an upper rotary member 43, a lower slide 48, and a lower rotarymember 52.

'Th lower rotary member 52 is inserted in an annular bearing 52:; abovea hole of the top plate 84 by means of a spigot 53. The bearing 52a has,been omitted in Figs. 6 and '7. The lower slide 48 is guided on thelower rotary member 52 by dove-tailed guides and supports, a spindle 49whose threaded portion engages in a female thread in a lug of the lowermember. The upper rotary member-48 has a spigot 41 engaging in a recessin the top wall of the lower slide 48. The topmost slide 4| is guided indove-tails 42 of the upper rotary member '48. This member supports aspindle 44 whose threaded portion engages in a female thread in 9. lugof the topmost slide. Clamping means I! are arranged for clampingtheupper rotary member 43 on the lower slide 48, and clamping means 80 areprovided for clamping the lower rotary member 52 on the top plate 54.Scales or other suitable means are provided for reading the positionsto. which the rotary members 52 and 43 have been rotated, and the slides48 and 4! have been shifted.

. A bearing for the upper end of a driving shaft 46 is arranged in' thetop wall of the lower slide 48 at the center of the spigot 41 for theupper rotary member 43. The driving shaft 48 is shown vertical'in Figs.6 and 7, in combination with horizontal slides, for the sake ofconvenience, but in fact, as shown in Fig. 11, the shaft and the slidesare arranged in planes inclined at 45 degrees. Keyed onthe upper end of.the driving \shaft 46is a bevel pinion 45" which meshes with a bevelpinion 45' on the spindle 44. The lower end'of the driving shaft 46 ismounted to rotate ale-moo of the'lower slide 46. 'I'heshafts 46 and IIare arranged in co-axial'relaiion. A bevelpinion II? at the upper end ofthe hollow driving shaft meshes with a bevel pinion Elf on the spindle46. *It will appear that the two co-axial drl 46 and 5| move with thelower slide 46, and this is why the opening 55 in the lowerend o1 spigot53 provides sufiloient space, o

The two driving shafts 46, it might be extended and equipped with shaftsand shifting the upper and lower shdes through their spindles 44 and 49.The hand wheels move with the lower slide 48 and this is notinconvenientif the distance through which the lower slide is is comparatively short.tances the hand wheels should be arranged in fixed positions, and nottravel with the lower slide.x Such an arrangement is illustrated inFigs. 6. 7. and 8.

pinion 6| at the lower end of the hollow shaft, and an annular washer 83in a groove of the shaft. The bevel pinion 6| meshes with a bevel pinion6|" is mounted to rotate in the-vertical arm of the bracket between theback of its bevel pinion 6|" and a. washer 84 in the hollow controlshaft. Mounted to rotate in theboss of the bevel pinion 6|" and'inco-axial relation to the shaft 66 is a solid control shaft 59 with abevel pinion 62" 62 on the lower 7 end of the solid driving shaft 46. Bythese on of rotation is effected from thesolid control shaft 59 to thesolid shaft 46, and from the hollow con shaft 66 to the hollow drivingshaft 5|.

This problem 'issolved by making the length of the cont i'ol shaftsvariable,'as shown in Fig. 7

connection of the control anditheir exits shafts, as indicated byswinging arm 61,

tensions, the control mechanism can adapt itself to all positions of thelower slide 46, and the driving shafts 46, 5|, transv y tothe axis ofthe arrowed arcs 86 about the axis 66-69, and longitudinally, asindicated bynthe arrows 86.

Mounted in a hearing at the upper end of the with their axis in the'axisM9 the arm swingsabout, are a solid controleoperating shaft 14, and ahollow controloperating shaft 15 surrounding "the solid control-opera onthe Shafts 74 and '15,

hand wheels or similar However, for longer dis:

.for the operator to eflect which-will be produced by on a hollowcontrol shaft 66 which .3- solid shaft 14. a pair of bevel gears 1r, 1|"connect thesolid controlshaft I! and tingshaft'llLandaplir ofbevel gears16', -16 connect the hollow control--.'

shaft 66' and the hollow control-operating shatt ll. 'Ihe hand wheelscan now be placed electing the most favorable conditions, extrahand-wheel shafts for the hand wheels 51 and II are mounted to rotate inplate I4. or, at the sides of the box |,.and connected to thecontrol-operating shafts 14, I6, or the shafts 14!, other bevel geartron, bevel gearlngs 16', 18" and 11', 11''.

since he cannot estimate the movement of a slide offthe slidesthemselves and of the iotar'y memwhere they are protected againstchina-dirt. and damage.

We claim: 1. In. a machine jecting intothegavity of the lower rotarymember means on one oi the driving shafts-for rotacuttingtoolandaworkpiecaatopplateforming part of thee tool, a hollowlower rotary member, a spigot on the lower rotary member lowerslidemounted to slide on the lower member,

or, if it is desired 10:"

16', connected'therewith by antool, means for holding acutting tool anda work piece, a top plate forming part of the machine tool, a

image against the T hearings on the top 10 on the otherdrlving shaft forrotating the other driving shaft, means for illuminating the tool: andthe work 5 1i! toturninaholeinthetopplate,a

' a spindleiorshifting the slide on the lower memco-axially the 7 bar,an upper rotary member mountedtorotateg on the lower slide, an upper.slide to which one of the parts is secured and which is mounted to slideon the upper rotary member, a spindle for shifting thisslide on theupper member, a solid and a hollow driving shaft mounted to rotate onthe lower slide in co-ax'lal relation to the upper rotary member and toeach other and projecting into the cavity of the lower, rotary memberwith a clearance, means on one of the driving shafts for rotating one ofthe spindles, means on the other driving shaft for rotating the otherspindle, a control shaft operatively connected to each driving shaft, abearing bracket mounted toswing about the hollow driving shaft forsupporting the control shafts, means for rotating each control shaft,means for illuminating piece at the point where the tool and the workthey engage, means fonmagnifying the shadow image of the profiles of thetool and the work piece which is projected-by such illumination at saidpoint, a screen, means for projecting the magnified image against thescreen, and a diagram of the profiles on the screen.

3. In a machine tool, means for holding a cut-'- ting tool and a workpiece, a top plate, forming part of the machine tool, a hollow lowerrotary member, a spigot on the lower rotary member arranged to turn in ahole in the top plate, a lower slide mountedto slide on the lowermember, a spindle for shifting this slide on the lower member, an upperrotary member mounted to rotate on the lower slide,

to slide on the upper rotary member, a spindle for shifting the slide onthe upper member, a solid and a hollow driving shaft mounted to rotateon the lower slide in co-axial relation to the upper rotary member andto each other and projecting into the cavity of the lower rotary memberwith a clearance, means on one of the driving shafts for rotating one ofthe spindles, means .on the other driving shaft for rotating the otherspindle, a control shaft operatively connected to each driving shaft,the two control shafts being arranged co-axially one within the other, abearing bracket mounted to swing about the hollow driving shaft forsupporting the control shafts, means for rotating each control shaft,means on each control shaft for varying its length in conformity withthe displacement of the driving shafts with the lower. slide, means forilluminating the tool and the work piece at the point where they engage.means for magnifying the shadow image of the profiles of the tool andthe work piece which is produced by such illumination at said point, ascreen, means forv projecting the magnified image against thescreen,rand a diagram of the profiles on the screen.

' 4. In a machine tool, means for holding a cutting tool and aworkpiece, a top plate forming part of the machine tool, a hollow lowerrotary member, a spigot on the lower rotary member arranged-to turn in ahole in the top plate, a

lower,slide mounted to slide on the lower mem-- ber, a spindle forshifting this slide on the lower member, an upper rotary member mountedto rotate on the lower slide, an upper slide to which one of the partsis secured and which is mounted to slide on the upper rotary member, aspindle for shifting this slideon the upper member, a solid and a hollowdriving shaft mounted to rotate on the lower slide in co-axial relationto its displacement with the .a lower slide mounted to an upper slide towhich one of the parts is secured'and which is mounted,

other and projecting into the upper rotarymember and to each other andprojecting into the cavity of the lower rotary member with a clearance,means on one of the driving shafts for rotating one of the spindles,means on the other driving shaft for rotating the other spindle, adivided'control shaft operatively connected to each driving shaft,telescopelike means connecting the parts .of each control shaft, an armmounted in the top plate to swing about an axis extending in parallelrelation to the axis of the driving shafts, a bearing in the arm for thereception of one of the partsof each control shaft, a bearing bracketmounted to swing about the hollow driving shaft and partaking inreception of the other part of each control shaft, means for rotatingeach control shaft, means for illuminating the tool, and-the work pieceat the point where they engage, means for magnifying the shadow image ofthe profiles of the tool and the work piece which is produced by suchillumination at said point, a screen, means for projecting the magnifiedimage against the screen, and a diagram of the profiles on the screen.

5. In a machine tool, means for holding a cutting tool and a work piece,a top plate forming part of the machine tool, a hollow lower rotarymember, a spigot on the lower rotary member arranged to turn in a holein the top plate, slide on the lower member, a spindle for shifting thisslide on the lower member, an upper rotary member mounted to rotate onthe lower slide, an upper slide to which one of the parts is secured andwhich is-mounted to slide on the upper rotary member, a spindle forshifting this slide on the upper member, a solid and a hollow drivingshaft mounted to rotate on the lower slide in co-axial relation to theupper rotary member and to each the cavity of the lower rotary memberwith a clearance, means on one of the drving shafts for rotating one ofthe spindles, means on the other driving shaft for rotating the otherspindle, a divided control shaft operatively connected to each drivingshaft, telescope-like means connecting the parts of each control" shaft,an arm mounted in the top plate to swing about an axis extending inparallel relation to the axis of the driving, shafts, a bearing in thearm for the reception of one of the parts of each control shaft, abearing bracket mounted to swing about the hollow driving shaftandpartaking in its movement with the lower slide, for the reception of theother part of each control shaft, a control-operating shaft allotted toeach control shaft, the two control shafts being arranged co-axially tothe. axis the arm swings about, and operatively connected to that partof the corresponding control shaft which is mounted in the bearing on'the arm, a hand wheel mounted to rotate in a position which is fixedwith respect to the top plate, for rotating each control-operatingshaft, means-lfor illuminating the tool and the work piece at the pointwhere they engage, means for magnifying the shadow image of the profilesof the tool and the work piece which is produced by such illumination atsaid point, a screen, means for projecting the magnified image againstthe screen, and a diagram of-,the profiles on the'screen. ALFRED KOLB.

WILHELM WILK.

lower slide, for the]

